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Ex-nurse gets 27 years for insulin murders

Hours after aged-care nurse Megan Haines discovered two elderly residents had complained about her, she injected the women with fatal doses of insulin.

"It was a gross breach of trust and a flagrant abuse of her power," said Justice Peter Garling before jailing Haines for at least 27 years for the murders.

"(Her) decision to administer insulin - a medication which is ordinarily meant to promote good health - in a way which was toxic and deadly, and in the setting of a facility which provides care for older citizens, is conduct which is almost too awful to contemplate."

The 49-year-old was found guilty of murdering Marie Darragh, 82, and Isabella Spencer, 77, in May 2014 at Ballina's St Andrew Village in northern NSW.

Haines had injected her victims with insulin between midnight and 1am on May 10, believing the drug to be undetectable as a cause of death.

Outside court, Ms Spencer's brother Donald said he was "over the moon" about the length of the sentence.

"I knew I would lose my sister sooner or later, but not in those circumstances," he said.

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Ms Darragh had complained about Haines refusing to give her a cream to soothe an itch, while Ms Spencer said she had refused to help her reach the toilet.

In setting a maximum of 36 years in the NSW Supreme Court on Friday, the judge said Haines had previously been suspended after complaints about her in Victoria.

She had only recently started work at Ballina and was subject to reporting conditions.

"(Her) motive to kill, namely that the victims had made complaints about her, was wholly insufficient and self-centred," the judge said.

"She thought that the deaths would appear to be from natural causes, as indeed they initially did."

The crimes were "particularly" serious cases of murder, he added.

"Each of the victims was vulnerable because of their advanced years, limited mobility, and limited capacity to detect what was happening, and to take measures to defend themselves."

Such conduct couldn't be tolerated and needed to be firmly denounced and deterred, Justice Garling said.

"It demonstrates a complete lack of respect for human life, a failure to recognise the dignity and integrity of older citizens, and a complete abrogation of the tenets of the caring profession of nursing which underpins so much good in society."

Haines' sentence is the third case of murder by insulin in a NSW court this month.

Sydney doctor Brian Crickitt was convicted of killing his wife while aged care worker Garry Davis was this week sentenced to a maximum of 40 years for murdering two patients and trying to kill another at a Newcastle home.